siding, railroad siding, turnout, sidetrack -- (a short stretch of railroad track used to store rolling stock or enable trains on the same line to pass)
siding -- (material applied to the outside of a building to make it weatherproof)
Overview of verb side
The verb side has 1 sense
side -- (take sides for or against; "Who are you widing with?"; "I"m siding against the current candidate")